Processing liquid hydrocarbons



March 4, 1952 w. w. WEINRlcH PROCESSING LIQUID HYDROCARBONS Filed Jan.5, 1950 Lira/WZL? GHS INVENTQR UIiHiam lll. 111m E SEER MISSOK WQNKPatented Mar. 4, 1952 UNITED STATES PATENT OFFICE y 2,587,669 PROCESSINGLIQUID HYDROCARBONSV William W. Weinrich, Wallingford, Pa., assignor toHoudry Process Corporation, Wilmington, Del., a corporation of DelawareApplication January 3, 1950,` Serial No. 136,444

(Cl. 19E- 52) 14 Claims. l

; The present invention relates to systems and methods for conversion orother processingy of hydrocarbons in contact with a granular contactmass and is particularly directed to improvements in the operation ofsuchV systems. wherein the granular mass is circulatedto andfrom areaction zone or treating zone. The invention is especially concernedwiththose systems and operations wherein the granular contact massduring such lcirculation iselevated fromv a lower to an upper level inthe system by a liftinguid stream.

Various hydrocarbon conversion. or treating operations employ systems ofthe type above designated; for example in. catalytic conversion ofhydrocarbons using a, moving bed of. adsorptive granular, catalystV asincracking', desulfurization, reforming. etc. Other operations coming intoconsideration include those whereina granular contactmasahaving littleor no catalytic activity, is. employed chiey as ameans of transferringcontained sensible heat to an oil to be processed, Whether for thepurpose ofthermally cracking or precoking the. oil, or for heating thesame to requiredreaction temperature or to vaporization temperature inthe caseof previously unvaporized liquid oils. While certain aspects ofthe present invention are applicable to operations. of the various typeshereinbefore designated, the inventionwill be more particularlydescribed in connection with the cracking of normally liquidhydrocarbons in contact with adsorptive catalysts to productsof.. vlowerboiling vpoint and lower molecular weight, such as products inthegasoline boiling range.

Normally liquid hydrocarbonswhen subjected to certainelevatedtemperatures, Whether or not in the presence of acatalyticallyactivemas's; break down to form solidcarbonaceous or'hydro-icarbonaceous deposits called coke As a general rule higher boilinghydrocarbons ata' givencracking severity display'a comparativelyAgreatertendency to form coke deposits. Where'such coke material isinherently orconcomitantly formed as a result of contact of hydrocarbonsat elevated temperature with catalyst or otherj adsorptive contact mass,the cokeable material is deposited in' the. contact Pmass, and can be'periodically apparatus. as a resultl of coke-producinghydrocarbonsremaining on the hot walls thereof, in many instancesconstitutes a .severe problem, oftento the extent of precludingpractical adapttion of a-processing technique that' would other-A wisebe highly desirable from the standpoint of enici'ency and economy ofoperation.

In catalyst circulatingsystems wherein the elen vationofthe catalystiseffectedby a vapor stream form, to take advantage of the heat contentof removed therefrom by transporting the' thus contaminated mass, in thecourse'fofits circulation, to a regeneration'zone' wherein the mass'iscontacted at ignition temperature'witlroxygen-con;-

taining gas to eiect combustion of the coke and resulting'restcraton ofthe mass forfrther'use in thehydrocarbon'processing'operation. Accu pmulationof coke'orrconta'ct mas'siwhich cannot besubie'c'ted toregeneration, or Vontp'ari';s"of"the l the catalyst for vaporization ofliquid, and"par` ticularly in handling of hydrocarbonswhichare notreadily volatilized below coking temperatures. These drawbacks arisingfrom coke accumulation when charging. non-vaporized hydrocarbons toavaporlift, are elciently overcome by vthe novel arrangement andoperating `method of the present invention.

` Inaccordance with the present invention,.cata lyst. or other hot.granular contact material is continuously. supplied 'to a .transferzone orhopper to form a bed of the material at the foot of andsurrounding a vertical lift conduit. A' gas or vapor lift medium ispasseddnto the bed ofV contact material under pressure so as to causeelevation of the contact material into the-left-conduit, andtransportation through that conduit. Hydrocarbons to be" converted orotherwise proc"- essed are admitted in liquid state directly within thelift' channel to engage the upwardly moving contact material therein.Within the lower p'ortion of the lift conduit and in' the region towhich the liquid hydrocarbons are admitted, the'contact material ispresent in comparatively high concentration and is moving in itsimpelled path constantly upwardly in the lift channel; there.. fore theliquidhydrocarbons are subjected to con# -ditions which favorcompleteand uniform distribution of liquid onthe contact mass. yBy oper-- atingin this manner the coke that may be formed. asa result of'subjecting theliquidhydrocarbons to the high temperatures prevailing in the'viciityofthe lift hopper, is depbsitedi or on 'thecoitact? material that is inipositive upward. motion and which' n' be subjected to' reg'eeltio'n'- BSrequired, thereby avoiding the possibility of forming interferingquantities of coke deposit within the lift hopper, as on the exposedwalls thereof or on any stagnant or relatively slow moving' contactmaterial that may be present therein.

In typical procedures directed to the preparation of a charge stock forcatalytic cracking, a bottoms fraction of crude oil or other highboiling fraction containing heavy ends which are not vaporized at theprevailing heating temperature, may be sent from the preheating furnaceto a flash distillation zone, providing a vapor effluent and a highboiling liquid fraction. The system and operation of the presentinvention are advantageously adapted to the handling of both the liquidand vapor products from such flash distillation zone. Conveniently suchvapor products may be employed as all or part of the lifting uid for thegranular contact mass, while theliquid hydrocarbons are introduceddirectly into the lift channel on the moving contact mass as aboveindicated. The vapor introduced into the transfer hopper for lifting orassisting in lifting of the granular solid contact material therein is,of course, not limited to such vaporous effluent from flashdistillation, and may be any gas or vapor not incompatible withhydrocarbons, but is preferably hydrocarbon vapor and/or steam. Whenhydrocarbon vapors are employed as lifting fluid or to assist in liftingthe granular catalyst or other contact mass, such vapors may compriseall or a part of the vaporous eiiiuent from a tar separator or otherflash distillation apparatus. The liquid hydrocarbons may comprise thenon-vaporized fraction from flash distillation, preferably free fromtars as such and from undesirable salts present in tar residues..Alternatively the liquid feed may be composed in whole or part of heavyliquid separated from products of cracking, either recycled from theparticular cracking operation or from some other source.

The operation of the novel features of the invention will be betterunderstood and other advantages thereof appreciated from the descriptionK which follows, read in connection with the accompanying drawingsillustrating several alternative embodiments adapted for practice of theinvention.

` Figure 1 is a schematic diagram of a systemA for circulating catalystor other contact mass, particularly illustrating the arrangement of thelift conduit and vessels directly communicating therewith.

Figures 2, 3 and 4 are enlarged partial views p'.

in vertical section of different modifications of details of thetransfer hopper and the lower portion of the lift conduit. Figure 5 isan enlarged view` of an additonal detail.

, vReferring now particularly to Figure 1, there i;-

is shown a transfer hopper I, into which catalyst or other solidgranular contact material is continuously admitted through a run downconduit 2, to form a bed within the hopper maintained at a substantiallyconstant level as indi- ,in a separating or disengaging vessel 5, whichvessel is provided with a discharge conduit 6 at or near the bottomthereof.

4 the lift conduit 4, above the bottom of that conduit. The conduit 4 issurrounded by a concentric sleeve or housing 8, which terminates at itslower end approximately at or near the level of the bottom periphery ofthe lift conduit 4. There is thereby formed between the outer wall ofconduit 4 and the inner wall of sleeve 8 an annular chamber 9, which isopen at its bottom end I0 and sealed at its top end I I. The top end ofthe sleeve is in communication with a vapor supply line I2. At an upperportion of the hopper I there may also be provided a vapor inlet line asindicated at I3 (see Fig. 3) for purposes which will hereinafter appear.It will be understood that the sleeve 8 may be formed in other thancylindrical shapes and need not completely sur- 'round the lift conduit.

, Details of the hopper I and its associated parts are better shown inthe enlarged views of Figures A liquid feed line 1 passes upwardlythrough the bottom of the hopper I and terminatespwithin 2, 3 and 4.Referring now particularly to Figure l2, as illustrated, the bottom ofhopper Ia is shaped to conform in contour substantially with the path ofiiow of the contact mass in the hopper when passing down the hopper andreversing direction to pass upwardly into the lift conduit 4. With ahopper bottom of approximately this shape the quantity of non-moving orrelatively slowly moving contact mass in the hopper is reduced to apractical minimum.`

The liquid feed line 1 may be simply a pipe having an open endterminating within the conduit 4 and discharging a stream comprisingliquid hydrocarbons into that conduit. If desired, the stream thusintroduced through line 1 may contain some vapor materials such as steamor vaporized hydrocarbons. In some instances it may be preferred todischarge the liquid hydrocarbons into ythe conduit 4 in atomizedcondition. One suitable arrangement for effecting atomization,accordingly, is illustrated in Figure 2 and shown in greater detail inFigure 5. Thus the feed line 1 may be provided with a T-coupling I1 orother pipe fitting having a lateral opening communicating with a liquidsupply line I8 and a connecting branch for reception of a vapor supplyline as shown for instance at I9. The vapor supply line I9 may beequipped with a discharge nozzle 20 of reduced cross section. Admissionof an atomizing gas or vapor through line I9 approximate theintersection of line I8 will cause atomization of the liquid introducedthrough line I8 and consequent discharge as an atomized stream throughfeed line 1.

In the operation of the embodiment illustrated in Figures 1 and 2 thelift vapors, such as steam and/ or hydrocarbon vapors are introduced atthe required pressure and in required quantity through line I2 into theannular zone 9 between the sleeve and the lift conduit. These vaporsflow downwardly in the annular zone and issue through the bottom I0 ofthe zone as an annular stream, which flows to a level somewhat below thelower end of conduit 4. These vapors then reverse their direction offlow and pass upwardly into the lift conduit 4. In doing so the vaporscontact granularL material from the bed in hopper I (or Ia) adjacent thelowerends of sleeve 8 and conduit 4, and lying in the vapor path,causing the granular material to pass beneath the lower periphery ofconduit 4 and upwardly into that conduit. The granular material is thenimpelled upwardly in the conduit 4 by the vapors passing through thatconduit, and is discharged from the upper end of the conduit into thedisengaging vessel 5. Because of the expanded cfiiss7` section@ oftheysseli 5;' the? vapors? dise" ed therein from conduit 4 losevelocity?to"l raniiiar material is-vfno longer f' an I the granularmaterial' iiieafbyeente'rsienteY seme extentte' cracked;

pese enligne which may' 'be steenr er1 other inert;-

gas; admitted" into the? catalyst inletfleg 2v may be 'introduced al? a'suitable" pressure so` that'r a portion of the` gas ilows'concurrentlywith"the' catalyst and down" that leg, entering the" space above vth'ecatalyst level in the hopper. Alternatively csi-"in addition-such sealgets-might be 111-' troduei' directlyintoth hopper above the cata# lystlevel by meansvof the valve-controlled inlet liii "|'3`.` The` use ofsteam for this purposeV has tla'dvantagvof providing at least a"po'rtioniolfv thef stanr that maybedesired to' be employedv aslprocss"stearii added to' the: hydrocarbonvconvex-i; Si'v reactiony Thevapors `el`i`i`g`th lift' conduit 4' together Witl' V'fp's f'r illthalt-C'Ondllit by'vaporz'ai#L tio'afl'coii'yesiohf (ifl the liquid feed'introduced 'tlll' w line-'1 aredischarged together" with thecataly'sti'ntothe disengagerv vessel 5. Unvapor.L Y liquid', if therebev any, Will be adsorbedon' the catalyst; and Will be Vvaporized orconverted byflni'i-rlinginContact with thecatalyst iii the'accumulated-bed thereofv formed in the'` Vessel-Y 5; during gravitationef that bea toward the die: charge outlet-of that' vessel; A'I'he' vaporproducts dirscliarg'*edatftlieV topY of'theY lift, pass dovvn wafmy'through the catalyst' benj inith'e vvessel-1 5 .are lSubjelctedj tofurther 'conversion theifebyf the" vaporous4 conyersion' products" beiigdischi A fromthecatalystin"passingover a'suitabl' solid-gas cisenga'gingmeans 211, whithnittype injtheforrn of 'a tubefv sheetlralfi'nrg'fshortdepeifiiI iiigtiibes thereiuer thefw'eii kiiettiitueur-tha 'f elsdS-enig'ager.' The vapors thus disengaged-are disohalfgdfrom the Vbottom of the? vessel 5 nby' Ineans'of a dischaigeiline 22from Which tlfieyfnov'lJ to apparatus for 'separation into desiredfractions and further'proces'sing as desired.. Below the'disfengagingmeans 21 the catalyst' enters'thedi'schargeconduitt through whichit'mayffloyv` to vt silitabliejl kilnfor regeneration by combustion' ofthefjcokein the catalyst. Before admission tothe kiln',` litHWilly beunderstood; the catalyst will be subjected to .a purging" operationtolremoveiesserbes iiquius' end tapers: The *eateiystinj di"- eliluentdischarged through line' Inivanyicase the catalyst is ultimately"regenerated`and?reL anular materiel wiir be' eti-a;

' maintained.

turned .inft regenerated forniv frein the kiln' through the' catalystinlet conduit 2-for repetition'Ezv of' the''described cycle.

In an alternative processing arrangement ernploying the apparatusillustrated in Figures 1 and2` the vaporsadmitted to the annular cham`ber'9f may.v consist of steam or lighthydrocarbon:

gases, and if desired crackable hydrocarbons may be admitted as theatomizing gas into the fitting Il through line IS.

admitted through line rI9;VA such steam assists in vaporization of theliquid hydrocarbons.

In `the modification shown in Figure 3 the lift gas,which mayY consistof or contain vaporize'd" hydrocarbons, is supplied principally througha jet'23 atthe bottom of the hopper l terminatingl in an outlet spacedvertically from the bottom of conduit 4 and providing therebetween a gap24 into which the granular mass continuously flows, and is picked up bythe ejected vapors discharged through jet23 and lifted thereby into th'econduitl Again, as inthe previously described:

ein' 'dimentg theA liquid hydrocarbons are" adrrii'tt'ed into the'liftconduit through the -liq'uid s'iipply linel l, which may be brought inconcentiicallyrthroughthelarger pipe 23, as illustrated.

or' may'beothervvise'lbrou'ght intoVv the hopper l'w poking' tendency'ascompared With the'less r ct''y heavy'ends of the oil, maybe intro'-duced through line I3, steam" rbeing 'introduced thi'ou'ghje't v23'. l

Instead of bringing the liquid feed in concentrically into thebottomofthe lift conduit 4, in anjalternative arrangement as illustrated'inigure 4 5 the liquid hydrocarbons may be introduced tliroughone or morelaterally intersecting pipes 2f-ata1ievel `abov'ethe bottom of the liftconduit; Such pipes 26 maybe simply provided with an open end'at thedischarge-outlet thereof into the conduit 4,'. 0r may be, equippedl Withscreened hea'dsio'r diffuser nozzles;

Asi'further` illustratedfin Figure 4, the" total reizl'uirem'ent oflifting' Vapor in arrangements employing the sleeve' 8V surrounding thelift con duitfll; need no'tlbesupplied through line l2, but an-auiiliaryvapor inlet may bei` provided, as shown at 27,1 to paesi' tapersyu'p'wetuiiy "through the catalyst' bed. Thus theY vapors admittedthrough? line 2T mingle withA the vapors discharged'fror'n the annular!'chamber 9 passing together-upwardly into the conduit'- 4 Vand eiect-lelevation ofthe vgnanular contact material ehgagedby thesevapors.I Byregulating the rate and quantity of vapors'l respectively v admittedtllrr'oughAlinesulgV and 2l ef'cient-'controlof the circulation ra'tofthe Contact vrmateriall can; b n y t I The vapori` introduced throughlines-{Zand- 27 lmay befof the same vor different composition for'instance' steam: maybe adriiitted thrt'rughv Jowneof these linesvandhydrocarbons vapors*throughftlfeiothen The line 21 may be amp'penfV'ended i pipe: or may 'be4 provided with Y a K In operations whereinhydro'"y carbons are admitted through-line I2 it may be preferred to`employ steam as the atomizing gasl 7 diffuser head of suitable design.As shown at 28, the discharge outlet of the pipe may be provided with asuitable baiile or screen to prevent granular ,material from fallinginto the pipe.

Common to all of the described embodiments, the introduction of the morereadily cokeable liquid hydrocarbons into initial contact with thecatalyst or other granular material takes place in the lift conduitproper or closely adjacent thereto in the channel traversed by granularmaterial that is already positively directed in its upward path forentry into the lift conduit, there by avoiding the possibility ofundesired coke accumulation within the hopper l (or la), and renderingunnecessary the elaborate precautions. that might otherwise be requiredto safeguard against the building up in a comparatively short period ofan accumulation of coke in the hopper to an extent interfering with thelifting operation. By restricting, the liquid introduction to the liftchannel and particularly to within the lower portion of the liftconduit, the liquid thus admitted contacts the -catalyst in (l)comparatively dense phase, yet (2) at a point or zone at which all ofthe catalyst is movingpositively upward in a path of xed lateralboundary delineated or prescribed by the diameter of the surroundingwall of the lift conduit. These two conditions prevailing at the pointor zone of liquid introduction are further explained below.

In a lift pipe of uniform cross section at a given mass circulationrate, the catalyst concentration at any level withinthe pipe will varyinversely with the catalyst velocity at that level. Just below theentrance to the lift pipe the catalyst is changed in its direction ofmovement and an upward force imparted thereto so thatthe catalyst isaccelerated in upward direction from zero velocity in that direction toa positive velocity during a comparatively short distance of travelwithin the lift conduit. The acceleration thentapers off, but thevelocity is progressively increasing to reach a, maximum at or adjacentthe top outlet of the conduit, so that the concentration of the catalystat a given uniform mass fiow rate is thus vconstantly decreasing.Accordingly the highest catalyst concentration within the lift conduitAprevails near the bottom of the conduit. The point of liquidintroduction between the ends of the lift conduit is preferably one atwhich the catalyst concentration is at least equal to 10% of theapparent bulk density of the catalyst in a random packed bed thereof. Byso choosing the point 0f liquid introduction, ordinarily, there willstill remain a path of travel of the catalyst or other contact masswithin the lift conduit of sufficient length to assure good distributionof the liquid on the upwardly moving granular mass, which liquid may beadsorbed therein or adhere thereto as -a surface film, and withouthaving free liquid as such discharged from the conduit, or remaining onthe walls of. the conduit to deposit coke thereon. The sameconsiderations apply in arrangements employing a lift conduit that istapered or otherwise constructed of increasing diameter in a directiontoward the top thereof. In such instances, however, although adequatecatalyst concentration may be had at levels higher up in the liftconduit than in the case of a lift of uniform cross-section, theintroduction ofthe liquid is preferably at a point sufficiently low thatthe liquid has adequate time and distance to become well distributed inthe catalyst prior to its discharge from the conduit, so that no liquidoil as such is carried over in thevdisengaging vessel 5.

It is also given as a, condition that theliquid introduction is at apoint or zone at which all of the catalyst is moving positively upward.I mmediately below the bottom of the lift conduit and over Ia shortprojected cross section of that conduit constituting a part of the liftchannel, positive movement of all the catalyst is established. The liftchannel therefore comprises not only the catalyst path within the liftconduit surrounded by the conduit wall, but includes a zone ofsubstantially the same lateral dimension for a short distance below thefoot of the lift conduit. This distance may vary to some extent with thevapor velocity and with the relative position of the bottom of thesleeve 8 with respect to the bottom of the lift conduit for this type ofvapor lift inlet; or mayvvary with the length of the gap 24 the types ofinletsystems illustrated in Figure 3. In either case the -zone in whichpositive upward movement of catalyst is assured includes that distancebelow the bottom of -the lift conduit proper, no greater thanapproximately one-fourththediameter of the lift conduit, which zone isthere fore embracedwithin the designation liftchannel. By thusdistributing the introduced liquid on the contact mass that hasenteredor is entering the'lift conduit, coke formed from lsuch liquid will becarried on the contact mass `and will be ultimately burned inregeneration of the mass. l

The total quantity of liquid hydrocarbons introdueed intotheliftcertainly should not exceed the amount that can be adsorbed by thecatalyst or` will adhere to the contact mass supplied'to the zone ofsolid-liquid contact. In practical operation, even in the case ofadsorbent catalyst, the point of saturation of the hot catalyst withliquid hydrocarbons, will not be the determining-factor in fixing themaximum ratio of liquid oil to cata-- lyst, since conditions of desiredheat transfer to achieve thermal balance in such practical operationsmay Vlimit the total amount of liquid that can be charged, to a figurewell below such point of saturation of the catalyst. For instanceatypical pelleted catalyst having a porosity say of 50 volume percentcan theoretically adsorbv an amount of liquid oil substantially equal toone half thel apparent pellet volume of the catalyst, given sucienttime,` and not taking into account continuous vaporization of theoilwith or without accompanying cracking. In practical operation, however,the amount of liquid oil charged should not exceed about. 1/3 of thecatalyst volume, and in fact taking into consideration the relativetemperature differential between the oil and the catalyst that is mostconvenient in such operation, and considering also the heat required andthe reaction temperatures desired to be maintained inthe principalconversion reactor, the amount of liquid oil charged vwill be preferablybelow 1/4 of the catalyst volume. The quantity of vaporized hydrocarbonscharged in addition to the liquid hydrocarbons, will depend upon theoperating conditions established for the principal reaction zone(compact movingA bedvreactor) including the selected catalyst to totalhydrocarbon ratio as one of `these conditions. Such additional vaporizedhydrocarbons may be introduced, entirely or onlyin part into the liftconduit, as previously described, to serve as lifting vapors,` andadditional hydrocarbons may be brought into the compact bed reactor, ifneeded to make up the required hydrocarbon to catalyst ratio.

9 Asa general rule, practice of the invention does .not necessitate adeparture from the usual processing conditions used in conventionalsystems lion carrying out hydrocarbon conversion reac- "tions, forinstance' those employing gravitating 4compact beds of catalyst or othercontact mass, as in catalytic cracking vvof hydrocarbons to gasoline',ycatalytic reforming ofV naphthas to products tof improved quality, orcorrespondingnon-catav lytic''operations wherein the 'granular' contact`'massis relied upon chiefly for heat transfer.

" ",As lcatalysts for hydrocarbon cracking operations there may beemployed'the known siliceous and other cracking catalysts includingacid-activated clay pellets or synthetic silica-alumina in the form ofcylindrical or spherical pellets (beads), of a size range designated asgranular as distinguished from nely vdivided powders 'of up to`100-200mesh size. Such granular catalyst or other solid contact mass ischaracterized bythe fprope'rty of forming compact beds throughwhichgase'sand vapors can be passed upwardly atpractical operating velocitywithout significantly disturbing the bed, as distinguishedfromnely di-"vide'd 'powders which are impelled or form.fluid vizedv bedsbyl.passage of gases or .vapors` therethrough at considerablylowervelocity. The granular catalyst or other contact mass employedinHpractice of the present .invention .should generjally .be of a sizegreater than about .05.-inch in .major dimension, and up ,toabout0.5,inch.

' Ininstallations wherein the chamber5 isemv.ployed to accumulatethecontact mass as a bed `'of ,suilicient height to serve as a gravitatingbed reactor, V.this chambershould .be `maintained,at,.suflicientpressure ,above atmospheric 'that the vapor. productsdischarged through line22 can be .sent to further processing withoutnecessitating pressure boosting. Generally the pressureat the `dischargeline 22should be in the order of at least about pounds per square inchgaugalso that .witha pressure-drop of about 4one pound or more throughthe bed in vessel 5, the pressure above the v,bed .wouldbe atleast 7.poundspersquare inchv or more. `llllicient andsmooth operation of thelift ,andadequate solids concentration` for adsorption of thefliquidhydrocarbonfeed is. generally had under conditions'providing a pressuredrop of vabout 1 .to about 12 pounds per square inchin `the A liftconduit 4, so that the. pressure in hopper I immediately below theconduit 4`Will be the sum Ao f .th e pressures prevailing at thedischarge end ...the lift conduit Zand Vthe pressure 'drop "in that fcduit. The required pressure in hopper I thereb determines the .pressurerof introduction of vapors throughline l2 or line 23.'

VThe disengaging vessel 5 need not be operated to ,accumulatea rbed ofgranular Contact material 1`,of"""sig`nicant` height."y For example, thetube r"sheetor other partitionfzl mayhie'omittedland the dischargeconduit 6 may be ofjsuch diameter as to'be `capable of. transport ing'the granular i'bon conversion reactor'as the granular mate- "yersionreactor, the4 pressure in the disengaging vessel should advantageouslybe higher thanV that `prevailing at the reactor inlet.`

ExamplmevI The following example illustrates a typicaloperation in thepractical yadaptation of the invention ,as applied to processing about2000 barrels ofpilwpe'r `day as fresh feed. The arrangement is based onthe use ofv a unit compri/sing" a'f12 --inch .diameter lift conduitofabo'ut`2'00 -feet inv height.

EastQTexas crude oilis fractionated and the bottoms fractionconstituting about"l0% of ylthe totalerude separated. Thisfractiomhavinga Agravity 01223.7" A. P. I. and an initial boiling pointItigres@ F., 80% boiling up to 1o14 F.; is admitted atappropriate'temperafure to a ilash yapori'zation zone, such as aconventional tar separator. operating at a temperature of 850 F. at apressure of about.17.5 p. s. i. gauge, steam being admitted to the zoneat the rate of Yabout- 24:37 poundsper barrel of oil charged. .Alloftheyaporizedhydrocanbonsand steam withdrawn overhead are sent tothe lifthopper .to operate as l'fapor lift medium, entering the hopper at aboutthe ash distillation temperature. The non-va- `'porizedhydrocarbons,constituting about 31.5% of the. oilcharged vto the lash vdistillationzone, are'removed as a bottomsifractionand sent toa .vacuum flash,distillation AZone toremove the heavytars and saltA contaminants.Theyauum distillation zone is. operatedatv a pressure Qf abeut 100. mm.of mercuryand steam isgaddedsthere to at .the .rateofapproxirnately 2.9pounds Aper -barrel of oil. `About one-,fthof the original 40% bottomsfraction. ofthe v crude oil, is dischargedas .taibottoms from the yacuum,distillati9n zone. while-.the o verhe'ad therefromis permittedtocondense and .pumped as liquid feed 2 3.4 A. `vPLI.

gravity)..to. the lift throughhline 1. @On the basis .oanl original2,000 barrelsper day charged to. the flash .distillationzona .this willprovide vfor vintro- '-.duc tion.in to thelift about 12,50 barrels ofhydro- .carbon yapors at lthe stated. temperature plusmthe .addedsteanrandiabout 3 50 barre ls Qfliquid feed at .about-,650 F. yFreshly.regenerated synthetic silica-aluminay bead catalyst at about 1 0 00f11'. en

ters thelift at arate giving aweight ratio.. of catalyst tooil of 6 tol. The pressureattheiootgof the. lift is maintained. at about 15. p.s..i. `gauge 1 and at thedischarge outlet ofthe lift,.in the dis-Cracked Products heavier than vg Lbs/Hr.

c; fre@ Gasoline (375 r. 90%).

C4 Cut Dry gas Coke burnoir 3. Barrels per stream. day.

In-the foregoingwexample a virgin oilffraction was charged as liquidyfeed toA the lift. .Inan al- VLternative operationlthe vapor overhead*from .the

rflash distillation zone is used -asflift mediums perdre,- biituuie1iduid.feed coiistitdts recycled are obtained the following products:

-Jdom packed volume of the granular contact mass.

eration is described in the following example.

amZeI Ex p I The catalytic gas oil is pumped as liquid and introducedinto the lift through line 1 at '700 F., the lift vapors from ashdistillation entering at about 850 F. Freshly regenerated syntheticsilica alumina bead catalyst is admitted to the hopper at 1000 F. orsomewhat above. Under approximately the same cracking conditions aSemployed in the previous example, but employing 625 bbls./day of liquidfeed at about 700 F., there BPSD Lbs./Hr.

C4 free gasoline (375i F. 90%

Catalytic gas oil (boiling above gasoline) C4 cut Dry gas Coke burnoiF., while in some cases the liquid feed may be attemperatures as high as900 F., or above. In certain operations-the entire liquid bottoms fromflash distillation may be sent directly to the lift Without removal ofthe heavy tars. Various other sources of liquid feed may be used, suchas slop oil from a lube refining operation.

Since the vaporization of the liquid hydrocarbons takes placeessentially within the lift conduit, the vapors thus produced do notsignicantly influence the catalyst circulation rate. Accordingly,uncontrolled changes in catalyst flow rate that might result fromvariation in the nature or condition of the liquid'feed, if it "werevaporized in the lift hopper, are avoided.

The term apparent bulk density as herein employed, has reference to theweight of a ran- In the case of silica-alumina bead catalyst of about0.12 inch diameter that has been in use 'andlmaintained at equilibriumactivity, the apparent bulk density is about 46 pounds per cubic foot.

Obviously many modifications and variations of the invention ashereinbefore set forth may be madefwithout departing from the spirit andscope thereof and therefore only such limitations should be' imposed asare indicated in the appended claims.

I claim as my invention:

1. The method which comprises continuously supplying hot granularcontact material to a transfer zone to form a compact bed of saidmaterial in said zone, passing a gaseous stream compatible Withhydrocarbons into said bed under pressureto cause elevation of a portionof the contact material and suspension in said gaseousA A stream,directing the gaseous stream and contact material suspended therein intoa vertical elongated channel commencing below the `top level of saidbed, flowing the gaseous stream past the contact material in saidchannel to impel the contact material vertically upward in said channel,admitting into said channel liquid hydrocarbons to directly engage theupwardly moving contact material therein, said liquid hydrocarbons beingadmitted to a lower portion ot said channel and in a region wherein saidcontact material is present in relatively high concentration as comparedwith higher regionsof said channel, whereby said liquid hydrocarbons arecompletely and uniformly distributed on said contact material, thecontact material in said bed and directed into said channel being at atemperature sufiiciently high to cause coking of said liquidhydrocarbons; whereby the coke produced as a result of conversion ofsaid liquid hydrocarbons at the temperature prevailing within saidtransfer zone and in said channel is deposited substantially entirely onthe moving contact material.

2. The method of treating liquid hydrocarbons which comprises engaginghot granular contact mass with a vapor stream to effect elevation ofsaid mass into and through an elongated vertical channel under theimpelling influence of said vapor stream, said vapor stream beingcompatible with hydrocarbons, distributing liquid hydrocarbon oil on thevertically moving contact mass at a level within said channel at whichsaid contact mass is present in suspension in the vapor stream in anaverage concentration of not less than 10% of the apparent bulk densityof said mass, said contact mass being at a higher temperature than saidliquid oil, transferring heat from the cont-act mass to the oil toeffect vaporization of the oil within said channel, discharging thecontact mass and oil vapors thus formed into an expanded disengagingarea, maintaining engagement between said oil vapors and said contact`mass thereafter to effect at least partial conversion of said vapors tolower boiling hydrocarbons, discharging the contact mass into a heatingzone and heating the same in said zone to restore the temperature ofsaid mass, and returning the thus heated contact mass to furthereng-agement with saidA elevating vapor stream.

. 3. The method in accordance with claim 2 wherein the quantity ofliquid oil distributed on said contact mass is not in excess of thatquantity which will be converted to vapors prior to discharge of saidcontact mass into said disengaging zone. y

`4. The method in accordance with claim 2 wherein said liquid oilcomprises hydrocarbons boiling above the range of gasoline.

5. The method in accordancev with claim 4 wherein a portion of said'hydrocarbons boiling above the range of gasoline are converted togasoline during contact with said contact mass, thereby concomitantlydepositing coke on said contact mass, and said heating of the contactmass in the heating zone is effected by combustion of the coke thereon.

6. The method in accordance with claim 2 wherein the quantity of liquidoil distributed on said contact mass is not in excess of one-third byweight ofthe contact mass.

7. The method in accordance with claim 2 wherein said vapor streamengaging said contact mass comprises hydrocarbon vapors fromdistillation of a liquid hydrocarbon oil fraction and said liquid oildistributed on said mass comprises at least a part of the unvaporizedresidue of such distillation.

8. The method of hydrocarbon conversion which comprises engaging a hotgranular adsorptive contact mass with a vapor stream compatible withhydrocarbons, to eifect elevation of said contact mass into and throughan elongated vertical channel, admitting hydrocarbons in liquid stateinto said channel to contact said granular mass for heat exchangetherewith thereby effecting at least partial vaporization of saidhydrocarbons within said channel, and separating the contact mass fromsaid vapors beyond said channel, said liquid hydrocarbons beingintroduced into said channel at a locus wherein the contact mass is inpositive upward motion and is present in suflciently high concentrationto adsorb the liquid hydrocarbons contacted therewith, and the sensibleheat content of said contact mass is sufcient to effect vaporization ofsaid liquid hydrocarbons and to eifect at least partial cracking of saidliquid hydrocarbons to lower boiling products.

9. The method of hydrocarbon conversion which comprises verticallymoving hot freshly regenerated granular cracking catalyst through anelongated transportation zone under the impelling influence of ahydrocarbon-containing vapor stream, the concentration of catalystwithin said transportation zone decreasing in the direction of movementof said catalyst, admitting hydrocarbons in liquid state within saidtransportation zone directly into contact with said vertically movingcatalyst and at a locus in said zone wherein the catalyst concentrationis at-least equal to of the apparent bulk density of the catalyst toeffect distribution of the liquid oil in the catalyst, said liquidhydrocarbons being at a temperature below that of the catalyst,maintaining contact between said liquid hydrocarbons and said catalystin said transportation zone for a time suiicient to eiect completevaporization of said liquid hydrocarbons by heat exchange with catalystwithin said transportation zone, and contacting the hydrocarbon vaporsthus formed with the catalyst beyond said transportation zone to furthercrack said vapors into lower boiling products with accompanyingdeposition of coke in said catalyst, regenerating the coked catalyst andreturning the regenerated catalyst for engagement with the transportinghydrocarbon-containing vapnr `stream.

10. The method of hydrocarbon conversion which comprises continuouslysupplying hot freshly regenerated granular catalyst at hydrocarbonconversion temperature to a transfer zone to form a compact bed ofcatalyst in said zone, passing a vapor stream compatible withhydrocarbons into said bed under pressure to effect elevation ofcatalyst from `said bed. directing said stream and the catalyst elevatedthereby into a conned vertical elongated transporting zone and owingsaid stream past the catalyst within said zone to impel said catalystvertically upward through said elongated zone to a disengaging zonewherein said stream and catalyst are separated, introducing hydrocarbonsin liquid state into a lower portion of said transporting zone and intoengagement with upwardly moving catalyst therein, maintaining contactbetween hydrocarbons and catalyst in said transporting zone for a periodsumcient to vaporize liquid hydrocarbons and partially convert vapor andliquid hydrocarbons to lower boiling products, and again contacting amixture of said vaporized hydrocarbons and lower boiling products thusformed with the catalyst after discharge into said disengaging zone toeffect further conversion of at least a part of said mixture into lowerboiling hydrocarbons; the catalyst being contaminated with coke formedby conversion of hydrocarbons in contact therewith, being then separatedfrom hydrocarbons and regenerated by combustion of the coke therein toprovide hot freshly regenerated catalyst at hydrocarbon conversiontemperature for supply to said transfer zone.

11. The method in accordance with claim 10 wherein said liquidhydrocarbons are introduced at a rate not in excess of the liquidhydrocarbon adsorption capacity of the catalyst at the temperature andcatalyst concentration prevailing in the region within said transportingzone wherein said liquid hydrocarbons are introduced.

12. The method in accordance with claim 10 wherein the rate ofintroduction of liquid hydrocarbons into said transporting zone isrelated to the rate that the catalyst is supplied to said zone and tothe heat content of said catalyst, such that the total heat content ofthe catalyst is suiHcient to supply theheat required for vaporization ofthe liquid hydrocarbons and for the endothermic heat of reaction for thesaid conversion of the hydrocarbons.

13. The method in accordance with claim 10 wherein said catalyst andsaid liquid hydrocarbons are supplied to said transporting zone at ratessuch that the weight ratio of catalyst to liquid hydrocarbons is atleast 3/ 1.

14. The method which comprises subjecting a heavy hydrocarbon oilfraction to ash distillation in the presence of steam to obtain a vaporeiiiuent comprising relatively light hydrocarbons and an unvaporizedliquid residue comprising relatively heavier hydrocarbons, introducingsaid vapor eilluent containing steam and said light hydrocarbons invapor state into a bed of hot freshly regenerated catalyst underpressure to impel catalyst from said bed upwardly into and through aconfined transporting zone, admitting at least a portion of saidrelatively heavier hydrocarbons in liquid state into said transportingzone to engage upwardly moving catalyst in said zone, said relativelyheavier hydrocarbons being admitted at a lower portion of saidtransporting zone and in a region therein-where the catalystconcentration is relatively dense, so that any liquid hydrocarbonsunvaporized by contact with the catalyst are adsorbed therein duringmovement o1' the catalyst in said confined transporting zone, andwhereby coke formed by conversion of hydrocarbons in said transportingzone is substantially entirely deposited on catalyst in saidtransporting zone.

WILLIAM W. WEINRICH.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 2,412,152 Hun? Dec. 3. 19462,437,222 Crowley et al. Mar. 2, 1948 2,440,475 Jacomini Apr. 27, 19482,487,961 Angell Nov. 15, 1949

2. THE METHOD OF TREATING LIQUID HYDROCARBONS WHICH COMPRISES ENGAGINGHOT GRANULAR CONTACT MASS WITH A VAPOR STREAM TO EFFECT ELEVATION OFSAID MASS INTO AND THROUGH AN ELONGATED VERTICAL CHANNEL UNDER THEIMPELLING INFLUENCE OF SAID VAPOR STREAM, SAID VAPOR STREAM BEINGCOMPATIBLE WITH HYDROCARBONS, DISTRIBUTING LIQUID HYDROCARBON OIL ON THEVERTICALLY MOVING CONTACT MASS AT A LEVEL WITHIN SAID CHANNEL AT WHICHSAID CONTACT MASS IS PRESENT IN SUSPENSION IN THE VAPOR STREAM IN ANAVERAGE CONCENTRATION OF NOT LESS THAN 10% OF THE APPARENT BULK DENSITYOF SAID MASS, SAID CONTACT MASS BEING AT A HIGHER TEMPERATURE THAN SAIDLIQUID OIL, TRANSFERRING HEAT FROM THE CONTACT MASS TO THE OIL TO EFFECTVAPORIZATION OF THE OIL WITHIN SAID CHANNEL, DISCHARGING THE CONTACTMASS AND OIL VAPORS THUS FORMED INTO AN EXPANDED DISENGAGING AREA,MAINTAINING ENGAGEMENT BETWEEN SAID OIL VAPORS AND SAID CONTACT MASSTHEREAFTER TO EFFECT AT LEAST PARTIAL CONVERSION OF SAID VAPORS TO LOWERBOILING HYDROCARBONS, DISCHARGING THE CONTACT MASS INTO A HEATING ZONEAND HEATING THE SAME IN SAID ZONE TO RESTORE THE TEMPERATURE OF SAIDMASS, AND RETURNING THE THUS HEATED CONTACT MASS TO FURTHER ENGAGEMENTWITH SAID ELEVATING VAPOR STREAM.